21354242475 has 48 divisors (see below), whose sum is σ = 36933778944. Its totient is φ = 10866240000.

The previous prime is 21354242473. The next prime is 21354242491. The reversal of 21354242475 is 57424245312.

It is not a de Polignac number, because 21354242475 - 2¹ = 21354242473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21354242473) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 676290 + ... + 707160.

It is an arithmetic number, because the mean of its divisors is an integer number (769453728).

Almost surely, 2^21354242475 is an apocalyptic number.

21354242475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21354242475 is a deficient number, since it is larger than the sum of its proper divisors (15579536469).

21354242475 is a wasteful number, since it uses less digits than its factorization.

21354242475 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31308 (or 31303 counting only the distinct ones).

The product of its digits is 268800, while the sum is 39.

Adding to 21354242475 its reverse (57424245312), we get a palindrome (78778487787).

The spelling of 21354242475 in words is "twenty-one billion, three hundred fifty-four million, two hundred forty-two thousand, four hundred seventy-five".